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Agar jelly diffusion experiement

Why would using larger agar blocks make the results more repeatable?

Answer is: Longer time is taken for the blocks to discolour, and so the % error is reduced.

However, I thought that larger blocks = larger SA:V ratio, so faster rate of diffusion meaning % error is increased?

Please explain where I've gone wrong. Thank you
Original post by Chem8585
Why would using larger agar blocks make the results more repeatable?

Answer is: Longer time is taken for the blocks to discolour, and so the % error is reduced.

However, I thought that larger blocks = larger SA:V ratio, so faster rate of diffusion meaning % error is increased?

Please explain where I've gone wrong. Thank you


Anyone there...
It would help if you post the whole question, but it looks as if you may have made a mistake in thinking that larger blocks have a larger SA:V ratio. The opposite is the case - small chunks have larger SA:V ratios than large ones.
Original post by OxFossil
It would help if you post the whole question, but it looks as if you may have made a mistake in thinking that larger blocks have a larger SA:V ratio. The opposite is the case - small chunks have larger SA:V ratios than large ones.



Ahh that's correct.. thank you!

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